1. Technical Field
The present invention relates to a driving force control unit for a vehicle which selects one driving force characteristic from a plurality of different driving force characteristics by manipulation (outside operation) and determines driving force based on the selected driving force characteristic.
2. Related Art
Conventionally, in an engine with a so-called electronically controlled throttle in which a throttle valve is electronically controlled using a throttle actuator, an accelerator pedal and the throttle valve are not mechanically linked and hence, opening of the throttle valve (throttle opening) can be controlled with nonlinear characteristic with respect to an operation amount of the accelerator pedal (accelerator opening).
For example, publication of unexamined patent application JP A 2005-188384 discloses a technology in which an operation state of an engine is divided into a plurality of operation regions based on an engine rotational speed and accelerator opening and a map is set for each operation region to perform control of the throttle valve conforming to the operation state of the engine.
According to the technology shown in the above reference, an appropriate map is automatically selected for each of the driving ranges, and the throttle opening degree is controlled in accordance with the selected map. In this case, high acceleration performance is requested when a vehicle merges into the main road of a highway or travels uphill road, that is, a driver is requested to push the accelerator pedal down.
However, the driver is requested to push the accelerator pedal to the metal so as to change the driving range to acceleration range, the driver feels a lack of acceleration by a response lag of reach to the acceleration range.